“I can sing better now,” the 59-year-old said in an early April phone interview. “I can play guitar better. I think some bands don’t do this. You can put that down to health. They get old, they get sick. We don’t do that. We get older, you can’t help that, but we still feel like we’re young.”

Collen, who’d played guitar early in his career for the glam band Girl, joined Def Leppard in 1982, when the band, one of the leaders of the new wave of British heavy metal, was in the middle of sonic turn that propelled it to international stardom.

That change involved adding elements of pop, glam and a little contemporary R&B with electronic drums and layers of harmonized vocals to its brand of metal – a sound that made its first definitive appearance on “Pyromania,” the 1983 album produced by Robert John “Mutt” Lange and the first Def Leppard disc on which Collen played.

“Mutt Lange deserves all the credit for that,” Collen said of the signature Def Leppard sonic amalgam. “It was his idea and him pushing us that far. We didn’t’ stay in the genre, we didn’t just listen to rock bands and use rock influences. What we did was incorporate what was happening at the time, whether it was pop or hip-hop turning into rap It really comes down to that, that open-mindedness.”

Fueled by the hit single “Photograph,” on which Collen played the guitar solo, “Pyromania” exploded, lifting the band from opening for Billy Squier to headlining stadiums, eventually selling more than 10 million copies in the United States, earning a diamond certification.

Then came “Hysteria,” another diamond album, released in 1987 after drummer Rick Allen lost his left arm in an automobile accident that forced another slight change in the band’s sound. That album generated seven singles as Def Leppard became one of the world’s biggest bands.

Def Leppard’s 2017 tour, which celebrates the 30th anniversary of “Hysteria,” stops at Citizens Business Bank Arena in Ontario Wednesday, June 14.

“You have to play the hot chestnuts, it’s a given,” Collen said about coming up with the set list. “There’s a bunch of them that are absolute essentials. Then there are second tier ones. And there’s a little bit of wiggle room for a new song or fun ones. But you have to play certain things or people are going to be pissed.”

That means it’s a certainty that concert goers will hear “Hysteria,” “Bringin’ On The Heartbreak,” “Pour Some Sugar On Me” and “Photograph” whenever Def Leppard hits the stage.

On the 2017 tour, Def Leppard will be preceded by Poison and Tesla, a lineup that Collen enthusiastically embraced.

“It’s fantastic,” he said. “We’ve toured with both bands before and love them. It’s almost like a celebration of integrity. We’ve got three bands with original members, not like some bands where there are just one or two. All these guys have been going, pretty much, at it as long as we have.”